站立负重CT分析外翻患者第1跖骨旋转的影响因素

Standing weight-bearing CT analysis of the first metatarsal rotation of hallux valgus patients

目的分析在正常直立负重状态下,外翻畸形患者第1跖骨旋转的影响因素。方法 2017年10月至2017年12月,在门诊选取30例(50足)连续就诊的外翻畸形患者,采用PedCAT进行负重CT检查,通过CubeVue软件系统进行重建。测量前足第1~2跖骨间角、外翻角等指标,于CT冠状横断面测量第1跖骨头的旋转程度,并记录跖骨是否存在圆角征。采用Pearson相关分析法分析各参数与第1跖骨旋转α角、正位和轴位籽骨分度的相关性。结果 50足均进行了负重CT检查,其中具有圆角征的足有42足(84%),43足(86%)旋前度超过正常参考值。平均第1跖骨旋转α角为(23.30±6.44)°,平均第1跖骨底边旋转角为(15.80±5.95)°,两者间有显著相关性,并存在线性关系。第1跖骨旋转α角与IMA角、正位Hardy-Clapham籽骨分度、DMAA角存在相关性,P<0.05。正位籽骨分度与IMA、HVA具有显著相关性(P<0.001),与DMAA、第1跖骨旋转α角、第1跖骨底边旋转角存在中等强度相关性,P<0.05。说明正位籽骨分度是重要的评价指标。结论第1跖骨旋前存在于大多数的外翻患者,它与IMA角、正位籽骨分度以及DMAA角存在相关性;跖骨底边旋转角可以反映第1跖骨的旋前程度。负重正位籽骨分度与外翻各参数都具有相关性,是外翻中重要的评价指标。

Objective Hallux valgus is consisting the pronation of first metatarsal in coronal plane.Our study was a research of relationship of first metatarsal rotation of hallux valgus in normal standing position with a standing weightbearing CT scan.Methods From October 2017 to December 2017,a cohort of patients were included into our research.These patients were 30 patients,50 feet diagnosed as hallux valgus.The full weightbearing CT scans were taken from PedCAT,and the results were processed with CubeVue software.Measurements of forefoot 1~2 inter metatarsal angle,hallux valgus angle,et al were recorded.The 1st metatarsal rotation angle was obtained from the coronal plane.The round corner sign was recorded too.All results were analysis with Pearson correlation.Results Fifty feet all finished weightbearing PedCAT scan,including 42 feet with round corner sign(84%),43 feet(86%)had a larger pronation angle than the reference data.Average first metatarsal rotationαangle was(23.30±6.44)°,and it is correlated to first metatarsal plantar margin rotation angle,which was average(15.80±5.95)°.In a linear regression model these parameters have a linear correlation.First metatarsal rotationαangle was correlated to IMA,Hardy-Clapham sesamoid classifacation and DMAA,P<0.05.Hardy-Clapham sesamoid classification is correlated with IMA and HVA significantly,P<0.001.And it is also has medium correlation to DMAA,first metatarsal rotationαangle,first metatarsal plantar margin rotation angle,P<0.05.This shows the importance of sesamoid position in hallux valgus deformity.Conclusion A large portion of hallux valgus patients has the first metatarsal pronation,and this pronation is correlate to IMA,Hardy-Clapham sesamoid classification and DMAA.This pronation can measured in two ways,and they are correlated significantly and have a linear regression relationship.Hardy-Clapham sesamoid classification is correlated to most of the parameters in hallux valgus deformity,its importance should not be neglect.